I. Field of Invention
This invention relates to telecommunications systems. Specifically, the present invention relates to systems for displaying performance characteristics of a code division multiple access (CDMA) telecommunications circuit.
II. Description of the Related Art
Wireless telecommunications systems are used in a variety of demanding applications ranging from search and rescue operations to business communications. Such applications require high performance cellular connections with maximum signal strength and reliability.
A CDMA network is separated into several geographical regions, i.e., cells, each region managed by a base station. The base station routes calls carried over cellular telephones, i.e., mobile stations, to and from a telecommunications network via a mobile switching center (MSC). The MSC routes calls among various base stations in the network, and to and from a public switched telephone network (PSTN), a network of conventional telephone lines.
Each base station has several cell site modems (CSM) which transmit and receive signals to and from mobile stations and other network entities. The performance of the CSMs must be accurately monitored so that transmission and reception problems are readily detected and corrected. CSM performance affects the performance of the entire CDMA network.
A CSM card may have a plurality of CSM chips, each having one or more CSM decoders, i.e., fingers used to decode incoming calls. The CSM chips are typically tested via the use of a Markov call. A Markov call is a cellular call that is used to measure transmission errors in a cellular communication system. A Markov call involves the transmission of a known mathematical pattern that simulates an actual call. By comparing the received signal with the expected signal, an accurate measurement of transmission errors may be made at the receiving end. These errors may then be traced back to a particular CSM chip.
To accurately monitor and tune the performance of a base station, the performance characteristics measured at a CSM chip may be measured. Performance characteristics of particular importance include CSM finger and peak data for a given Markov call. The finger data includes the signal strength of the incoming Markov call at each of the CSM fingers in a given test set of CSM chips. The peak data includes signal peaks received by the CSM fingers.
CSM finger and peak data may be used to verify proper CDMA antenna installation. For example, if a receive antenna at a base station is tilted incorrectly, the CSM chips associated with a call through that antenna will have different finger and peak data than that of a correctly installed antenna. If antennas at a base station are properly installed and tilted, they are said to be balanced.
Typically, accessing finger and peak data requires the use of a temporal analyzer. A temporal analyzer is typically difficult to read and uses an excessive amount of transmission bandwidth. Hence, a single collection of finger and peak data from a given base station often takes several hours using a conventional temporal analyzer.
Hence, a need exists in the art for a user friendly system for displaying CSM finger and peak data resulting from Markov call testing. There is a further need for an efficient system and method for determining base station antenna balancing.